This is the resubmission of an application for the Lead Clinical Center for the Study of Asthma and Nasal Steroids; it is linked to the Data Coordinating Center application submitted by Dr. Robert Wise from the Johns Hopkins Bloomberg School of Public Health. Asthma is a significant public health problem in the United States and poor asthma control is associated with significant morbidity and health care utilization. An important factor that may contribute to poor asthma control is disease of the nose and sinuses. The American Lung Association-Asthma Clinical Research Centers is a network of 20 academic research centers. Results from trials completed by ALA-ACRC have identified rhinitis and sinusitis as a significant cause of co-morbidity that affects asthma symptoms and control. The objective of the proposed clinical trial is to determine if treatment of chronic rhinitis and sinusitis will improve control of asthma. Although chronic rhinitis and sinusitis have been associated with poor asthma control and increased health care utilization, the effect of treating these diseases on asthma control is not known. We propose a six-month randomized, double-blinded, placebo-controlled trial enrolling 380 participants with poorly controlled asthma and chronic rhinitis/sinusitis. We will use a sensitive and specific tool, developed by us, to identify chronic rhinitis and sinusitis in people with asthma. Participants will be randomized to receive nasal steroid or matching placebo in addition to their regular asthma treatments. The primary objective of the trial will be to evaluate whether the addition of treatment with nasal steroids improves asthma control. We will perform allergy skin testing on all participants, and keep a record of pollen counts at all centers, to determine if allergy is an important factor in the response to nasal steroid in participants. The ALA-ACRC network is uniquely positioned to determine the effect of treating chronic rhinitis and sinusitis in asthma; results of the current proposal will provide significant new data to guide therapy in patients with poorly controlled asthma. Asthma is a major public health problem in the United States. Rhinitis and sinusitis may lead to worsening of asthma. The aim of the current proposal is to determine if treatment of rhinitis and sinusitis will improve asthma control - results of this study will guide therapy in patients with poorly controlled asthma.